Technically that sounds illegal so be careful. All the books are copyrighted and I assume it's illegal to reproduce them in any form.
If I made the website publicly available, then I'm sure there would be major issues. But it's for my own use, and only I have access. I didn't "reproduce" anything, it was already in a digital format; I simply changed the medium on which that is available. And since I've been doing it for the better part of 4 years, I'm not too worried :)
Always good to be cautious of such things though.
Chad